Pneumatic engine or motor.



PNEUMATIC ENGINE OR MOTOR.

APPLICATION FILED Nov. 14. 1914.

f Patented Aug. 14,1917.

H. GIBBS.

PNEUMATIC ENGINE 0R MOTOR.

APPLICATIION FILED NOV. 14. 1914.

Patented Aug. 14, 1917 3 SHEETS SHEET 2.

Fill

H. GIBBS.

PNEUMATIC ENGINE OR MOTOR.

v APPLICATION FILED NOV. 14, I914. 1,236,922. Patented Aug. 14,1917.

3 SHEETS SHEET 3.

1'5 j, y 49 4 i g Q. 2 lg: 22

HARRY GIBBS, OF HIGHER TBANMERE, ENGLAND.

PNEUMATIC ENGINE 01R, MOTOR.

Specification of Letters Patent.

Patented Aug. 14, 1917.

Application filed November 14., 1914. Serial No. 872,242.

To all whom it may concern.

Be it known that I, HARRY GIBBS, a sub ject of the King of GreatBritain, and a resident of Higher Tranmere, Cheshire, England, haveinvented certain new and useful Improvements in Pneumatic Engines orMotors, of which the following is a specification.

The present invention relates to improvements in pneumatic engines ormotors and more particularly to the valve mechanism of the same wherebythe apparatus may be converted from a single stage compressor into afluid pressure engine, and vice versa.

The apparatus according to the present invention may be used as a brakeand restarter for internal combustion engines, whether stationary orapplied to road or rail vehicles of any description. When in use as abrake the machine is coupled to the engine shaft, or alternatively tothe road wheels and will then be acting as a single stage compressor andwhile it is being driven is compressing air into a tank or reservoirprovided for this purpose. The valve mechanism is preferably providedwith a control intermediate the valves and the crank shaft so that ondisplacement of the control mechanism when the fluid pressure engine isrequired to act as a re-starter, compressed air from the tank orreservoir will be allowed to act upon each piston of the cylinders ofthe engine in succession, causing the machine to work as a motor.

In the preferred form, each cylinder of the engine is provided withthree valves, one of which, controlling the passage between thecylinders and the tank or compressed air reservoir, is preferably of theautomatic type. The second set of valves, preferably of the puppet valvetype, control passages leading from the cylinders to the atmosphere. Athird set of valves, preferably arranged around the spindles of saidpuppet valves, are adapted to close the outer end of these passagesleading to the atmosphere when the puppet valves are lifted off theirseatings to an extraordinary extent, which. latter motion is such thatthe automatic valves are also raised off their seatings preferably bythe direct action of the puppet valves thereon. The present inventionwill be more particularly described with reference to the accompanyingdrawings illustrating one form of construction by way of example,

Figure 1, shows a sectional elevation of the crank case of an engineaccording to the present invention with one of the cylinders inposition.

Fig. 2. is a section through the cylinder of the device showing valves,the section being taken at right-angles to the position of the cylindershown in Fig. 1.

Fig. 2 is an enlarged view illustrating the packing 28, together withits adjusting means.

Fig. 3. shows diagrammatically the position of the valve parts when thedevice is acting as a single stage compressor.

Fig. 4. shows the valve position on a portion of the inlet strokecorresponding to Fig. 3.

Fig. 5. shows the valve positions when the device is being used as afluid pressure motor when the particular cylinder is on the exhauststroke.

Fig. 6. shows a condition of working simi lar to Fig. 5. when the pistonis on its working stroke.

A plurality of cylinders 1, preferably three or more to avoid a deadcenter, are arranged in any desired position vertically, horizontally,or preferably radially as shown, mounted upon a crank case 2. Thecylinders 1 are provided with pistons 3 connected by the usualconnecting rods 4 to crank'pins 5 on a crank shaft 6 mounted in bearingsin the crank case 2. The crank shaft 6, in the case taken by way ofexample in which the device is used in conjunction with the internalcombustion engine of an automobile or like vehicle, preferably hasmounted upon it a clutch member which can be thrown into or out of gearas desired with the crank shaft of the engine of the vehicle. The crankshaft 6 has a cam 7 keyed thereto or arranged integrally therewith, andthis cam 7 is adapted to cooperate with valve tappet levers 8 mountedupon a plate 9 slidable about the crank shaft 6. The position of theplate 9 relatively to the crank shaft 6 can be adjusted by means of astud or handle 10 which works in a slot 11 in the crank case, the endsof which slot preferably act as stops for limiting the end positions ofthe plate 9.

The tappet levers 8 are preferably provided with anti-friction rollersat one end engaging the face of cam 7 and may be of any desired form,that shown being particularly suita le for the arrangement of valve.

illustrated in the other figures of the drawings. The tappet levers 8are freely pivoted on pins 12 carried by the plate 9. The tappet levers8 are held in gear with the cam 7 by springs 1-? one end of each ofwhich enters a hole in the plate 9, the springs being coiled about thepivots 12. The tappet levers 8 operate directly upon tappets 12 mountedin spindle bearings in the crank case 2 in the usual manner.

The valve arrangement according to the present invention consists ofthree sets of valves. The first set comprises automatic valves such asball valves 15, Fig. 2, controlling a passage 16 communicating through apassage way 17 Fig. 1, with a storage tank or vessel for compressed air.The valves 15 are held on their seatings by springs 37 inclosed in caps18 screwed into. the cylinders 1. The second series of valves comprisespreferably puppet valves 19v controlling the passage between thecylinders 1 and the atmosphere. These valves 19 have their shanks orspindles preferably squared or fluted for a certain distance. The. stems20 of said valve s act in direct conjunction with the tappets 14. Thevalves 19. are normally held on their seatings by springs 21 arrangedbetween the valve casing of the cylinders 1 and a collar 42 of usualform on the valve spindles 20.

The third set of valves is in the form of tubular sleeves such as 22provided internally with packing 23 which may be adjusted by means of ascrew 24. This tubular valve 22 abuts normally against the lower end ofthe squared or fluted portion of the spindles 20, but when the valves 19are raised into their outermost position farthest away from theirseatings upon the cylinder 1, the valves 22 may come into contact withseatings on the cylinder 1 and consequently prevent leakage of air. fromthe cylinder to the atmosphere down the spindles 20 of the valves 19.The valves 22 are held tightly against the shoulders on the valves 19"oralternatively against the seating on the outer surface of the cylindercasings by springs 25 arranged between the valves 20 and, for instance,the collars $2 on the valve spindles 20.

The upper ends of the valves 19v are preferably arranged with portionssuch as 26 adapted to come into engagement with and lift the automaticvalves 15 from their seatlngs.

The cylinders l, in addition to the ports 27 communicating withpassages, as above described, controlled by the valves 15 and 19respectively, are provided with a series of ports 28 which are sodisposed that they are uncovered toward the end of the stroke of thepistons. These ports communicate with the atmosphere through the crankcase When it is desired to use the arrangement as a single stagecompressor or a brake for any moving shaft such as has been suggestedabove by connecting the crank shaft 6 to the wheels of an automobilevehicle or the like, then the shaft 6 will be clutched suitably to suchshaft to be braked or from which power is to be obtained andconsequently the pistons 3 will be reciprocated in their respectivecylinders 1.

F or this purpose the stud or handle 10 is displaced into the positionindicated by A in Fig. 1 of the drawings. This will bring the plate 9into such a position that the tappet levers 8 willall be clear of theirrespective tappet spindles 14 Consequently rotation of the crank shaft 6and of the cam 7 will have no effect upon the valves controlling thepassages in communication with the cylinderlj Consequently will be seenthat the puppet/valve will remain seated during the whole cycle. On thesuction stroke of the. pistons in each cylinder 1 a partial vacuum willbe created in cylinder so that as the piston passes below the ports 28air will pass into the cylinder. from the crank case. The piston on itsre.- turn stroke will compress the charge ofair lying. between the ports28 and the passage 27 and directly compression exceeds the pres; sure ofthe spring 37 holding the automatic ball valve 15 upon its seat, thislatter. will be lifted so, that the compressed air will pass through thepassage 1T to the tank or reservoir in communication therewith. Ifdesired, the control may be so. disposed that instead of the puppetvalves remaining seat ed for the whole cycle, the cam will lift the sameto provide a freev inlet during certain moments of thecycle. This is thepreferred form.

In certain cases it may be desirable with the mechanism as shown toobtain a slightly increased charge over that possible by only allowingthe vacuum in the cylinder. to be released when the pistons move belowthe ports 28. Consequently if desired the handle 10 may be brought into.the position B indicated in Fig. 1. Then as may be. seen from Fig. atthe levers 8 will all be displaced to such an extent that when the liftportion of the cam comes into contact with the tappet rollers the valvespindles 20 will indeed be raised to lift the valve 19. in its seat butnot sufficiently to raise the valve 15,. Conse quently as the pistons inthe cylinders move. down atmospheric air will be drawn through thepassage controlled by the puppet valve 19. h hy P i'W QQ -W ta d, is ftd jus off its seating and, it is to. be noticed, not sufficiently toallow the tubular valve 22 to. close this passage with the atmosphere.Then the piston passes the ports 28 afur ther supply of air may passinto the cylinder 1, completing the. charge. On the upstroke of thepiston the valve 19 will go back on its,

seating so that when the air is compressed to the predetermined degreeit will pass beyond the valve 15. The spring 37 on the valve 15 may incertain cases if desired be arranged so that its tension may beregulated from the outside. For instance, this may be effected byscrewing up to a greater or less degree the caps 18. It is obvious thatthe pressure of the other springs may be regulated in a similar manner.

In the case when it is desired for the device to act as a fluid pressuremotor, for instance as a re-starter for the engines of automobiles, theplate 9 is moved by means of the handle 10 until this latter comes intothe position C indicated in Fig. l of the drawiii-gs. The tappet levers8 will then be moved under the tappet spindles 14 to their full ex tent,the upper surfaces of these tappet levers 8 which cooperate with thetappet spin dles let being preferably cam shaped to provide the effectdesired cooperating with the lifting cam 7. In this position of theparts, one of the valves 15 will be lifted off its seating while theothers, in the present instance three, will be in the position illustrated in Fig. 5. The valve which is lifted off its seating will be inthe position illustrated in Fig. 6, so that compressed air can passthrough the passage 17 under the automatic valve 15 now raised andthrough the passage 27 into the cylinder 1 so that the piston whichwill, of course, be at the top of its stroke in this cylinder, will thenbe forced downward, turning the crank shaft and whatever machinery is incommunication therewith, such, for instance, as the crank shaft of theautomobile engine which it is desired to turn for the purpose ofrestarting. As this piston moves down under the pressure of thecompressed air and the crank shaft 6 turns, the cam 7 will no longerhold the tappet lever 8 in a raised position to the degree shown in Fig.6, but this will fall into the position shown in Fig. 5, wherebycommunication between the reservoir and the cylinder is now interruptedby the valve 15 returning on its seating, while the valve 19 will belifted ofi its seating, but the passage between the cylinder 1 and theatmosphere will be closed owing to the tubular valve 22 closing thispassage beneath the squared portion underneath the valve 19. The exhaustof the compressed air in the cylinder will take place through the ports28 at the bottom of the stroke.

When the device is running as a re-starter or motor in certain cases itmay be desirable to arrange the cam 7 of such contour that the tappetlevers 18 Will drop sufiiciently to allow the automatic valves 15 tore-seat themselves and then a further amount sufficient to lift thetubular valve 22 off its seating but not suficient to re-seat the valve19 so that air in the cylinder on the upstroke can be exhausted firstlythrough the ports tappets engaging the positively operated valves, and acam fixed on the crank shaft adapted to actuate the tappets.

2. In a pneumatic engine or motor, in combination, a series ofcylinders, a crank shaft, pistons in said cylinders operatively coupledto said crank shaft, a storage tank, spring valves controllingcommunication between the cylinders and said storage tank, positivelyoperated valves controlling communication between the cylinders and theatmosphere, spring valves also controlling communication between thecylinders and the atmosphere, and closing permissively by the openingmovement of the positively operated valves, a series of pivoted tappetsengaging the positively operated valves, and a cam fixed on the crankshaft adapted to actuate the tappets.

3. In a pneumatic engine or motor, in combination, a series ofcylinders, a crank shaft, pistons in said cylinders operatively coupledto said crank shaft, atmospheric ports in the cylinders adapted to beuncovered by the movement of the pistons, a storage tank, spring valvescontrolling communication between the cylinders and said storage tank,positively operated valves controlling communication between thecylinders and the atmosphere, a series of pivoted tappets engaging thepositively operated valves, a cam fixed on the crank shaft adapted toactuate the tappets, and means for varying the movement imparted by thecam to the tappets.

1. In a pneumatic eng ne or motor, in combination, a series of radiallydisposed cylinders, a crank shaft, pistons in said cylinders operativelycoupled to said crank phere and closing permissively by the openingmovement of the positively operated a ves, Plate angu a y a j stable abthe crank shaft, a series of tappets pivoted on said plate, a cam fixedon the crank shaft adapted to actuate the tappets, and means o adjust nghe angular positi f e tappet plateto vary t e efi t w action the cam,

5. I a P umatic engine or mo or, i m inat on, a series o radial y posylind s, cr nk s aft, pist ns n sai cylinders operatively coupled tosaid crank shaft, atnlOspheric ports in the cylinders adapted to beuncovered by the movement of the pistons, a storage tank, spring valvescontrolling communication between the cylinders an s id rage nk, p s i yoperated valves controlling communication bebetWeen the cylinders andthe atmosphere,

spring valves also controlling communication between the cylinders andthe atmos phere and closing permissively by the opening movement of thepositively operated valves and opened. by the closing movement of thepositively operated valves a plate angularly adjustable about the crankshaft, a series of tappets pivoted on said plate, cam faces on thetappets, a cam fixed on the crank shaft adapted to actuate the tappets,and means for adjusting the angular position of the tappet plate to varythe effective action of the 0am.

In testimony whereof I afliX my signature in presence of two Witnesses.

HARRY GIBBS.

Witnesses i A. J. DAVIES,

R. S. JoNns,

Copies of this patent may be obtained for five cents each, by addressingthe Commissioner of Patents. Washington, D. C.

